In the manufacturing and processing of sheetlike material, it is often necessary or desirable to inspect such material for the purpose of detecting any defects in the material before it is shipped to the customer or utilized in further process steps. Thus, in the textile industry, it is common practice for predetermined lengths of fabric to be passed over an inspection board, which may be provided with backlighting, to permit an operator to visually inspect the fabric as it is moved along the surface of the inspection board.
Typical apparatus utilized for this purpose includes a frame having a pair of spaced elements for rotating the spindle of a fully wound roll of fabric and an empty spindle is rotatably mounted in the frame to permit the cloth to be wound thereon as it is unwound from the full roll. A generally flat inspection board is mounted in fixed relation to the frame above the two spindles, and a plurality of idler rollers, usually four, are rotatably mounted in the frame, two being located at the ends of the inspection board to provide a smooth flow of fabric across the flat surface of the inspection board, and two being located between the inspection board and the two spindles to guide the fabric in its path of movement towards and away from the inspection board, and to impose the desired tension on the fabric as it moves across the inspection board.
In utilizing this conventional inspection equipment, a full roll of fabric is manually carried to the frame and mounted thereon for rotation, and the exposed end of the fabric is manually pulled by an operator to partially unwind a length of the fabric, and the operator then manually threads the fabric end around and over the plurality of idler rollers and over the surface of the inspection board until the end is finally wound onto the empty spindle. The operator then energizes a drive motor which rotates the empty spindle to pull the fabric across the surface of the inspection board to permit inspection of the fabric by the operator. It will be appreciated that this manual threading of the fabric end about the several idler rolls and the inspection board is time consuming, usually taking almost half of the total time required to complete the entire inspection cycle of a typical roll of fabric, usually between 7 and 10 minutes depending on the motivation of the operator. Also, since the full rolls of fabric are quite heavy, it is common practice for one relatively strong employee to be assigned the task of manually carrying the full rolls to a plurality of inspecting frames, and additional time may be lost in waiting for the delivery of a full roll to an inspecting frame that is otherwise ready for operation.
In an effort to maximize the efficiency of the inspection process, the full rolls are usually wound with as much fabric as possible to reduce the number of threading operations which must be carried out each time a roll is exhausted. Therefore, the full rolls are as heavy as will be permitted for manual carrying of the full rolls to and from the frame, and it is therefore desirable to locate the supports for the rolls at or near the bottom of the frame to reduce as much as possible the necessity that the heavy full rolls be lifted to an elevated position. On the other hand, since the fabric is to be visually inspected, it is desirable to locate the inspection board at an elevated position in the frame so that it will be at the approximate eye level of the operator standing adjacent to the frame. This results in a relatively substantial spacing between the spindles and the inspection board, which increases the time required to manually thread the fabric through the inspection frame at the beginning of each cycle.
In accordance with the present invention, the aforesaid drawbacks of conventional inspection apparatus are alleviated by a unique arrangement that reduces significantly the time required to carry out the inspection of fabric as well as the manual operations associated with such inspection.